This invention relates generally to rigid adjustable length assemblies and more particularly, but not by way of limitation, to a rigid adjustable length manifold assembly for rigidly connecting two objects of a fluid-delivery system, which objects can be spaced at different distances and orientations relative to each other at a well site.
At a well site where an oil or gas well has been drilled, for example, there is often the need for injecting a fracturing fluid into the well and the surrounding formation to enhance the flowability of the formation. One specific substance which is used as a fracturing fluid is liquid carbon dioxide contained at the well site in large storage receivers which can hold, for example, fifty to sixty tons of liquid carbon dioxide per receiver. Several of these receivers can be located at a well site, and we are aware of at least one location where up to fifty-eight of such fifty to sixty ton receivers have been used.
From these receivers, the carbon dioxide is pumped at a temperature of between +20.degree. F. and -20.degree. F. and at a pressure of up to approximately 500 pounds per square inch (psi). If a break should occur in such a system, the liquid carbon dioxide escapes into atmospheric conditions and rapidly changes state to vapor and solids.
Obviously, there is the need for some type of safe system for conveying such a substance as the liquid carbon dioxide from the receivers to the well. Present systems of which we are aware use flexible hoses often connected in series between each of the receivers with wing nuts or the like. We are aware of occurrences where either the wing nuts have failed or the flexible hoses have ruptured, thereby allowing the liquid carbon dioxide to spew out and rapidly form a blinding vapor cloud. The vapor cloud impedes shutting down the broken portion or the overall system. In those instances where the hoses are connected in series, the entire system must be shut down even though only a small part may have been ruptured or broken; additionally, the flowability of the sysem is limited to the capacity of the serially connected hoses. Furthermore, when flexible hoses are used, the result is often an intertwined mass of hoses which hampers both shutdown and detection of the specific ruptured or broken portion.
Although flexible hoses may present certain problems in a fluid delivery system of this type, they do permit easy coupling of the parts within the system which are at variable distances from each other. Additionally, flexible hoses compensate or allow for relative movement between the coupled parts, such as between an operating pump and a stationary conduit supplying the fluid to the pump.
Therefore, there is the need for a fluid delivery system which has parallel-connected rigid interconnections for properly conveying fluid and for relatively rapidly and easily permitting controlled shutoffs should a portion of the system be damaged. Furthermore, there is the need for such a system with rigid interconnections to provide, despite the rigidity of the individual elements, for compensating between differences in distances and orientations between different equipment or parts of the system and for compensating for relative motion between parts of the system while the fluid is flowing therethrough.